Microbial Profile of Suya Meat in Enugu State
Chapter One
AIMS AND OBJECTIVES
This work is aimed at determining the microbial quality of suya meat sold in Enugu and has the following objectives:
- To isolate, characterize and identify microbial species associated with Suya meat.
- To establish the public health implication of consumption of Suya meat.
- To offer useful information where necessary to the consuming public.
CHAPTER TWO
LITERARURE REVIEW
SUYA MEAT
Suya meat is a traditional stick meat product that is commonly produced by the Hausas in West Africa from beef, although chicken can also be used. It is produced from boneless meat hung on stick and spiced with peanut, cake, salt, vegetable oil and other flavor followed by roasting around a glowing charcoal fire. The smoke from the fire has a preservative effect on the Suya meat (Ogunbanwo et. al. 2004).
PREPARATION OF SUYA
Usually in Nigeria, skinless, boneless flesh of cattle or chicken is used for commercial preparation of suya meat. Finely grounded roasted peanut cake, red pepper, salt, grounded ginger, grounded garlic, chunked fresh tomatoes and minced fresh onions are required on suitable conditions depending on the quality of suya meat required to be prepared (Jay, 2000; Judge et. al.2000).
The process of preparation involves a few steps, first is the grounding of peanut. The shell and the skin are removed from the peanut before grinding into fine powder using mortar and pestle or crushed with a rolling pin. If the powder is oily; it is wrapped with an absorbent paper and squeezed for a minute or two. Next, the grinded pepper, garlic, ginger are stirred into the obtained peanut powder and mixed properly.
The meat is then cut into bit sizes or thin sliced, dipped and rolled in a bowl containing the mixed peanut-spice and allowed to coat completely. The minced or mutton meat are then kept for thirty minute or more for the peanut cake to stick to it after which the meat slices are threaded unto skewer and brushed with vegetable oil and roasted on the glowing charcoal fire for fifteen to twenty minute. It is finally removed from the skewer and served hot in a newspaper with sliced onions, tomatoes and cabbage (Judge et. al.2000).
MICROBIOLOGY OF MEAT.
Microorganisms destroy the inherent defense mechanism of the animal thereby subjecting the tissue to rapid decay as a result of its action (Lidwell et. al. 1996).
During slaughtering process, there is contamination of the sterile tissue with intestinal flora like gram-negative organisms which includes Escherichia coli as well as contaminants such as Pseudomonas specie and gram-positive lactic acid bacteria and Staphylococci specie associated with human, animals and their environment. Meat spoilage is usually associated with gram-negative Proteolitic bacteria which literally decompose the protein with production of offensive odour (Hamman, 1997).
The addition of salt and drying of fresh meat have been an effective means to control the meat micro flora and thus preserve the tissue for later consumption. The curing salt (sodium chloride, sodium nitrate and sodium nitrite) and subsequent proper handling methods, favours the growth of gram-positive bacteria, primarily Staphylococcus aureus while inhibiting the proliferation of gram-negative bacteria (Boles et. al. 2000).
There are also other types of common microorganisms apart from enteric organisms found in meat which are members of Micrococcaceae and Staphylococcaceae families. The predominant types are coagulase-negative Stapylococci that are salt tolerant and can also grow with or without oxygen. The most common strain belongs to the species of Stapylococcus carnosus, S. xylosus and S. kocuria variance by far. However, these organisms are harmless and do not present a microbial hazard. The most common lactic acid microorganisms found in fermented meat of various strains of Lactobacilli, Leuconostoc, Pediococci, Streptococci and Enterotocci (Lawries, 2001).
CHAPTER THREE
MATERIALS AND METHODS
MATERIALS
CHEMICAL AND REAGENTS
(1) Crystal violet
(2) Iodine
(3)Acetone (alcohol)
(4)Safranine
(5) Oil immersion
(6) Normal saline
(7) Hydrogen peroxide
(8) Distilled water
(9)Oxidase reagent
(10) Christensen’s urea broth
(11) Simon’s citrate agar
(12) Acetymythyl carbinol
(13) Buttered glucose broth
(14) Nepthol
(15) Sodium hydroxide
(16) Glucose phosphate peptone
(17) Methyl red
(18) Peptone water
(19) Tryptophan
(20) Kovac’s reagent
(21) Sugar solution
(22) Glucose
(23) Sucrose
(24) Lactose
(25) Mannitol
SAMPLES COLLECTION
Twenty skewers of suya meat were obtained randomly from suya vendors at popular suya spots in Enugu. The samples were immediately wrapped in sterile aluminum foil to prevent contamination and then transported to the laboratory for microbial analysis without delay.
CHAPTER FOUR
RESULTS
Suya samples collected randomly were carefully analyzed, the charaterization and identification result is presented on table 2. The isolates were identified as Staphylococcus 35%, Pseudomonas 35%, Streptococcus 15%, and Escherichia coli 15% The most frequently isolated organism was Staphylococcus and Pseudomonas species. The total viable count ranged from 1.9x – 3.8x . whereas total coliform count ranged from 1.1x-3.0x as shown in table 1.
CHAPTER FIVE
DISCUSSION, SUMMARY, CONCLUSION AND RECOMMENDATIONS. DISCUSSION
Meat basically contains all the nutrients necessary for microbial growth and metabolism, making it susceptible to microbial contamination. In view of the material quality of meat and meat products must be ascertained to ensure safety from infection after consumption of such products and to promote quality assurance.
Laboratory analysis carried out on suya meat was collected randomly suya vendors in Enugu, Enugu state. Some microorganisms were isolated, in which the result was in consonance with the literature of Chukwura and Majekwu(2002) which stated microbiological analysis of meat samples in Awka urban Anambra state, indicated contaminated of meat sample with various bacteria species including Staphylococcus aureus, and some enteric bacteria Gilbert Harrison(2001)also affirm that meat contains certain amount of salt by so permit the growth of Staphylococcus aureus whereas, the presence of some members of the enteric bacteriacea family is due to contamination from intestine slaughtered animals.
Four organisms were isolated from the suya sample in view of the of the unhygienic condition of meat handling in Nigeria, the organisms isolated could always be suspected in connection with meat contamination and spoilage. The organisms include Staphylococcus specie, Streptococcus specie, Escherichia coli Pseudomonas specie.
The presence of Staphylococcus specie affirms the cross contamination through processing (Gilbert and Harisson 2001).Since it is normal flora of the skin. Raw meat is usually carried on the body by butcher in Nigeria due to lack of education (Dada et.al; 1993). Confirmed that coliform often results from the water used for washing the meat which of course is always contaminated.
Also presence of Escherichia coli probably may arose from the use of non –portable water during washing of raw meat (Umor,2004).
The meat also showed presence of pseudomonas aeruginosa, which usually occurs around soil, vegetation and even surface (Field, 2002).
On the whole, the critical points of contamination of suya meat are roasting, handling and reheating. So control contamination of contamination can be achieved if aseptic techniques of suya preparation process are observed.
SUMMARY AND CONCLUSION
Suya meat constitutes a great source of protein which is needed for body building and repair of worn out tissue in human. Advances in the microbial quality of suya meat is very important and adequate steps must be taken to prevent contamination and spoilage by microorganisms.
The organisms isolated from the suya meat indicate that the standards of preparation and preservation have not improved much over the years and facilities used for preparation are not sterile. Aseptic techniques are not adequately employed in the meat industries as so to reduce microbial load of meat and its products for safety consumption by consumers and thus prevent food-borne diseases or infections.
RECOMMENDATIONS
Quality control unit should established in meat processing industries in Nigeria and Hazard Critical Control Point ( HACCP) concept should be applicable to the processing and renderings.
REFERENCES
- Abdul, U.M., Beuchat, C.R., and Ammar, M. S. (1993).Survival and growth of Escherichia coli in ground roast beef as affected by pH, acidulates and temperature. Journal of applied and environmental microbiology 59(8): 2364-2368.
- Alexander, J.W.,Jacob, L.S., and Nicholas, B.N. (1998). Incidence of enterobacteroria in meat processing. Journal of Food Science 27:177
- Ayres, C.P. (1985). Microbiology of spoilage food and food stuffs. Journal of food microbiology 16: 206-212.
- Boles, J. A., Rathgether, B.M. and Shand, P.J.(2000). Staphylococcus in salted meat product. Journal of meat Science 55: 223-231.
- Buchanan, R.E. and Gibbons, N.E. (1994). Bergeys manual of determination Bacteriology. 8th Edition. The Williams and Wikins Co, Baltimore. Pp. 5-10.
- Cannon, J.E., Morgan, J.B. and Mcketh, F.K. (1997). Meat contamination and poisoning. Journal of muscleFood 7:29-36.
